I recently had a problem with an ABM trussrod on a custom neck I built.

I had to remove the ebony fretless fingerboard.
Here is my method (note that it relies on the glue type used for glueing the fingerboard - in my case, standard yellow titebond).

You will nedd a sharp knife, 95° or more alcohol and a brush.
At the body end of the neck, start applying alcohol with the brush on the glue joint. When the glue starts to disolve, gently insert the knife on the joint. Then, the job is only a matter of patience because you'll have to keep applying alcohol in the joint, moving the blade towards the nut, hammering it slowly on each sides.

If you take your time, you'll remove the board with no crack, just ready to re-glueing after the alcohol has evaporated.

Note that some company can install leds into your neck without fingerboard removal. It's a safer method because, removing the board the way I've just explained is a bit risky with a fretted one. Chances of breakin the board at a fret slot could be great, depending on the fgbd thickness and wood...

Originally posted by JP Basses
Note that some company can install leds into your neck without fingerboard removal. It's a safer method because, removing the board the way I've just explained is a bit risky with a fretted one. Chances of breakin the board at a fret slot could be great, depending on the fgbd thickness and wood...

I generally remove fingerboards with a clothes iron. Apply heat long enough and the glue will start to run. I generally forget about trying to use the old fingerboard again. They tend to bend as they come off.

Removing a fingerboard is not easy however you do it, and you run a risk of damaging the neck.